This invention relates to the field of pipe cleaning generally. More particularly, it relates to the method and apparatus of cleaning pipe such as pipe located in a sub-sea location, wherein concrete or the like is removed from the pipe by the present apparatus and method.
With increased production of oil and gas and the like in off-shore locations or in sub-sea locations, it is becoming more necessary to install pipelines for the purpose of transporting such fluids, quite often requiring the laying of pipeline along underwater locations. It is usually necessary to coat such pipe with a heavy external coating of concrete or the like in order to cause the pipe to remain in the submerged location rather than floating to the surface. Quite often, coated pipe of this type becomes damaged, either through natural forces acting on the pipe or through accidents, such as anchor damage by vessels utilizing the water space above the pipe. When damage to the pipe occurs, it may be necessary to cut out the damaged section and replace the damaged section with a spool of new pipe. In cutting out the damaged section and replacing it with a spool, it is necessary to clean the adjacent ends of the undamaged pipe so that the spool may be properly attached to the undamaged pipe. In addition, it is also necessary to have means for severing the pipe in the underwater location so that the new spool may be inserted and connected to the undamaged ends of the pipe.
Heretofore, repairs of the foregoing type have been very difficult and were usually made by divers descending to the level of the submerged pipe and carrying on the repair operation by hand-held tools, which, of course, was very inefficient, dangerous and time consuming, and impossible in some instances. Another method has been the lowering of a large bell-type habitat which would completely surround the area and provide workmen with a dry habitat in which to carry out the repair operation. Again, this is quite expensive and impossible in some instances.
It is, therefore, an object of this invention to provide an improved method and apparatus for the cleaning and repair of pipeline such as a submerged pipeline in a difficult working environment, which method, if desired, may be carried out remotely from the surface of the water, for example.